Cable Management Assemblies for Electronic Appliances

ABSTRACT

A laminate curtain can suppress electromagnetic radiation leakage from an electronic appliance, as well as assist in managing cables interconnected to the electronic appliance. More specifically, a laminate curtain can include a conductive elastomer panel that absorbs spurious electromagnetic radiation generated by the electronic appliance, a conductive adhesive film disposed along one side of the conductive elastomer panel, and a conductive support frame affixed to the conductive adhesive film. The laminate curtain can be installed within a mounting frame, which secures the laminate curtain to the electronic appliance. Electromagnetic radiation that is absorbed by the conductive elastomer panel can travel to the electronic appliance via the conductive adhesive film, the conductive support frame, and the mounting frame. Thus, the conductive elastomer panel can be used to form a ground plane that catches and shunts the spurious electromagnetic radiation to the electronic appliance, which is grounded.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 62/545,085 titled “Cable Management Assemblies Having Side CurtainsFor Network Communication Systems” and filed on Aug. 14, 2017, which isincorporated by reference herein in its entirety.

FIELD OF THE INVENTION

At least one embodiment of the present disclosure pertains to assembliesfor managing cables connected to an electronic appliance and suppressingelectromagnetic radiation leakage from the electronic appliance.

BACKGROUND

Electromagnetic interference (EMI) is a disturbance that affectselectrical components (e.g., integrated circuits) by electromagneticinduction, electrostatic coupling, or conduction. At high levels, EMImay degrade the performance of electrical components or preventelectrical components from functioning entirely. Man-made sources andnatural sources can generate the changing electrical currents andvoltages that cause EMI. Example of man-made sources include computerservers and other networking devices configured to filter, manipulate,and/or route traffic traversing a computer network.

Electromagnetic (EM) shielding is the practice of surrounding anelectronic component with a conductive or magnetic material to guardagainst incoming emissions and/or outgoing emissions of electromagneticfrequencies (EMF). A number of different materials are conventionallyused for EM shielding. For example, wires may be surrounded by metallicfoil that blocks errant EMI. As another example, audio speakers mayinclude an inner metallic casing that blocks EMI produced by theinternal drivers. These materials prevent the EMI from affecting othernearly electronics (e.g., a mobile phone, radio, or television).

Conventional EM shielding technologies are becoming less effective asdata transfer speeds increase. In order to increase the data transferspeed of an electronic appliance, the transmission frequency must alsoincrease. However, increases in transmission frequency can greatlyelevate the electromagnetic radiation generated by the electronicappliance.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the present invention are illustrated by wayof example and not limitation in the figures of the accompanyingdrawings, in which like references may indicate similar elements.

FIG. 1 depicts an example of an electronic appliance that is capable ofreceiving an enclosure that includes one or more laminate curtains.

FIG. 2 depicts an example of an electronic appliance having bracketssecured thereto.

FIG. 3 depicts an example of a laminate curtain that can be installedwithin a mounting frame.

FIG. 4 depicts an exploded view of a cable management assembly that canbe secured to an electronic appliance adjacent to the interface surfaceto which cables can be connected.

FIG. 5 depicts an example of an enclosure that includes multiple airfilters and multiple EMI suppression panels.

FIG. 6 depicts a laminate curtain installed within a mounting frame.

FIG. 7 depicts a front perspective view of the laminate curtain prior toinstallation within the mounting frame.

FIG. 8 depicts a rear perspective view of the laminate curtain prior toinstallation within the mounting frame.

FIG. 9 depicts an example of a laminate curtain for suppressingelectromagnetic radiation leaking from the chassis of an electronicappliance.

FIG. 10 illustrates typical reflectivity curves of several differentradiation-absorbing panel materials.

FIG. 11 illustrates how cables connected to the interface surface of anelectronic appliance can be routed through perforations in a laminatecurtain.

FIG. 12 illustrates how the slots in a laminate curtain can form aseries of flaps, which seal as much as possible to ensure maximumcapture of electromagnetic radiation leaking from the electronicappliance.

FIG. 13 depicts a flow diagram of a process for manufacturing a laminatecurtain able to suppress electromagnetic radiation leaking from thechassis of an electronic appliance.

FIG. 14 is a block diagram illustrating an example of a processingsystem in which at least some operations described herein can beimplemented.

DETAILED DESCRIPTION

Telecommunication and networking environments have become increasinglycomplex over the last decade. However, the basic design of theelectronic appliances used in these environments has become fairlystandardized.

For example, the chassis of an electronic appliance is typicallydesigned such that the chassis can be installed in a rack following awell-developed set of standards defined by the InternationalElectrotechnical Commission (IEC). An example of an electronic applianceis a computer server.

The front panel of such a chassis can include an interconnect interface(also referred to as an “interface surface”) to which one or more cablescan be connected. These cable(s) can include copper-based cables and/orfiber optic cables. Thus, when the chassis is installed in the rack, thefront panel typically has cable(s) dressed horizontally to the left sideand/or the right side of the chassis. The cable(s) can then be directeddownward toward a cable trough below the floor or upward toward a cablerunway above the rack.

Air is often guided through the chassis to cool the electronic applianceduring operation. However, the air must be filtered to prevent theaccumulation of dust, which can cause damage to the electronic appliance(e.g., by causing a fire). Chasses can be designed so that a chassis canbe cooled using one or more fans positioned near the rear of thechassis. Such a design is referred to as a “front-to-back airflowmodel.” The alternative design (i.e., the bottom-to-top airflow model)is less prevalent. While bottom-to-top airflow models do not experiencethe same airflow challenges as front-to-back airflow models,bottom-to-top airflow models can still experience similar issuesregarding the leakage of electromagnetic radiation.

Electronic appliances must be able to meet several performance standardsand requirements. For example, an electronic appliance may be requiredto conform to Federal Communication Commission (FCC) requirements forelectromagnetic interference (EMI), radiation immunity, etc. EMIrequirements ensure that the electronic appliance does not radiateexcessive amounts of electromagnetic radiation that could adverselyaffect nearby electronic equipment, while radiation immunityrequirements ensure that external radiation cannot enter the electronicappliance and interfere with performance.

In some instances, the electronic appliance will also need to complywith Telcordia Network Equipment-Building System (NEBS) guidelines.Compliance with NEBS guidelines is typically certified by an independenttesting laboratory, such as National Technical Systems (NTS) orUnderwriters Laboratories (UL). NEBS is a common set of guidelinesapplied to some types of electronic appliances (e.g., telecommunicationsequipment) to establish criteria for various operating environments andevaluate performance over a wide variety of conditions.

Meeting these various requirements can be difficult, so designers andmanufacturers of electronic appliances must execute at a high level toachieve a passing result. Several factors have made passing results moredifficult to achieve in the last several years. For example, as the datatransfer speed of an electronic appliance increases, the transmissionfrequency will also increase. Consequently, an increase in data transferspeed will be accompanied by a proportional decrease in the wavelengthof electromagnetic radiation generated by the electronic appliance.Because shorter wavelengths can more easily escape openings in achassis, high-speed electronic appliances are more likely to experienceelectromagnetic radiation leakage.

Although completely-sealed chasses can prevent such leakage,completely-sealed chasses suffer from several additional issues. Forexample, a completely-sealed chassis will prevent air necessary forcooling from flowing through the electronic appliance. Moreover, thecompletely-sealed chassis will prevent the electronic appliance frombeing maintained and/or upgraded over the course of its lifetime throughthe implementation of replaceable components.

Consequently, developing an electronic appliance design that can achievea passing result usually requires a combination of different solutions.Some of these solutions are based on containing electromagneticradiation within the electronic appliance, and thus tend to involvecomplicated shielding and gasketing techniques that ensure theelectronic appliance operates within the allowable limits.

Because new electronic appliances often operate at the edge of theseallowable limits, a small margin is available to compensate forvariation in electronic appliances. Examples of variations includevariations in manufacturing, chassis design (e.g., the number ofconnectors along the front panel), signal strength (e.g., due to theactual signals being processed), data transfer speed, etc. For example,if an end user causes a 100-gigabit electronic appliance to subsequentlybecome a 1,000-gigabit electronic appliance by replacing one or moreplug-in modules, then the 1,000-gigabit electronic appliance is unlikelyto still operate within the allowable limits.

Introduced here, therefore, are laminate curtain assemblies thatsuppress electromagnetic radiation leakage from an electronic appliance.The laminate curtain assembles can also block air from circumventing airfilter(s) disposed along a side of the electronic appliance, therebyensuring that the air must pass through the air filter(s) beforeentering the electronic appliance. The laminate curtain assemblies canalso assist in managing cables interconnected to the electronicappliance.

More specifically, a laminate curtain can include a conductive elastomerpanel that absorbs spurious electromagnetic radiation generated by theelectronic appliance, a conductive adhesive film disposed along one sideof the conductive elastomer panel, and a conductive support frameaffixed to the conductive adhesive film. The laminate curtain can beinstalled within a mounting frame, which secures the laminate curtain tothe electronic appliance. Electromagnetic radiation that is absorbed bythe conductive elastomer panel can travel to the electronic appliancevia the conductive adhesive film, the conductive support frame, and themounting frame. The conductive elastomer panel can be used to form aground plane that catches and shunts the spurious electromagneticradiation to the electronic appliance, which is grounded.

Terminology

Reference to “one embodiment” or “an embodiment” means that theparticular feature, function, structure, or characteristic beingdescribed is included in at least one embodiment of the presentdisclosure. Occurrences of such phrases do not necessarily all refer tothe same embodiment, nor are they necessarily referring to alternativeembodiments that are mutually exclusive of one another.

The terms “connected,” “coupled,” or any variant thereof includes anyconnection or coupling between two or more elements, either direct orindirect. The coupling/connection can be physical, logical, or acombination thereof. For example, two devices may be physically,electrically, and/or communicatively coupled to one another.

General System Overview

FIG. 1 depicts an example of an electronic appliance 100 that is capableof receiving an enclosure 108 that includes one or more laminatecurtains 106. As shown here, the enclosure 108 can be securely mountedto one or more brackets 104A-B disposed along opposing sides of theelectronic appliance 100. The bracket(s) 104A-B may also be referred toas “vertical chassis mounting rails” or simply “chassis mounting rails.”The bracket(s) 104A-B can be affixed to the chassis of the electronicappliance 100 or a rack within which the electronic appliance 100 ismounted.

Cables typically tend to be connected to the electronic appliance 100through the use of connectors disposed along the front panel or the rearpanel of the electronic appliance 100. Here, for example, the electronicappliance 100 includes multiple connectors arranged along an interfacesurface 102. This allows for great flexibility in making the necessaryconnections from a variety of interconnection types. For example,copper-based cables for power, control, and/or signaling can beinterconnected to electrical connectors along the interface surface 102.Additionally or alternatively, fiber optic cables may be interconnectedto optical connectors along the interface surface 102. Each electricalconnector and optical connector along the interface surface 102corresponds to an opening in the chassis of the electronic appliance 100through which electromagnetic radiation can escape.

The electrical appliance 100 may also be cooled during operation. Thus,one or more openings may be created along the air inlet side(s) and theair outlet side(s) of the electrical appliance 100, thereby effectivelycreating a duct for cooling. For example, a fan disposed near the rearof the electronic appliance 100 may be arranged to draw air in throughopening(s) along the interface surface 102 and expel the air throughopening(s) along the rear panel of the chassis. The opening(s) may bedesigned to maximize the availability of air and limit leakage ofelectromagnetic radiation. For example, the size and/or number ofopenings may be limited to ensure proper attenuation of electromagneticradiation. As another example, an EMI suppression panel may at leastpartially overlap an opening to prevent electromagnetic radiation fromleaking through the opening.

Containment of electromagnetic radiation can become more complicatedwhen the interconnection(s) between the electronic appliance 100 andother pieces of electronic equipment are addressed. Many electronicappliances not only require a large number of connectors (e.g., alongthe interface surface 102), but also as many openings for ventilation ascan be provided. Powerful fans may be required to move air through thelimited ventilation area in the electronic appliance 100. Generally, airis circulated through the electronic appliance 100 on the order ofhundreds of cubic feet per minute.

Cables connected to the interface surface 102 must also be managed sothat the cables themselves do not become a hindrance to air flow. Thelaminate curtain(s) 106 may aid in guiding any cables connected to theinterface surface 102 of the electronic appliance 100 into a verticalchannel positioned alongside the electronic appliance 100. For example,a cable may extend through a perforation in a laminate curtain 106.Generally, vertical channels are created between adjacent racks thateach include one or more electronic appliances.

The enclosure 108 can include a top panel, a bottom panel, and a frontpanel that connects the top panel to the bottom panel. The laminatecurtain(s) 106, meanwhile, may be arranged along opposing ends of theenclosure 108. Together, the laminate curtain(s) 106 and the enclosure108 may form a substantially-sealed chamber adjacent to the interfacesurface 102 of the electronic appliance 100. In some embodiments, asingle laminate curtain 106 is disposed at one end of the enclosure 108,while a side panel is disposed at the opposite end of the enclosure 108.The side panel may ensure that one end of the enclosure is completelysealed.

The enclosure 108 may also include one or more air filters 110A-B (alsoreferred to as “air filtration panels”) that are configured to filterair entering the electronic appliance 100. The air filter(s) 110A-B aregenerally disposed within the front panel of the enclosure 108 if theelectronic appliance 100 is a front-to-back airflow mode. However, theair filter(s) 110A-B could also be disposed within the top panel or thebottom panel of the enclosure 108.

Thus, the entire three-dimensional (3D) space in front of the interfacesurface 102 of the electronic appliance 100 can be used for airfiltration, electromagnetic radiation suppression, and cable management.The laminate curtain(s) 106 located within the cable transition region(CTR) are able to address each of these problems.

The CTR is where horizontally-directed cables that are connected to theinterface surface 102 turn into the vertical channel positioned adjacentto the electronic appliance 100. Historically, the CTR has been poorlymanaged. For example, conventional electronic appliances may address airfiltration but not electromagnetic radiation suppression, or vice versa.In fact, conventional electronic appliances typically allow unfilteredair to flow through the CTR, which permits unfiltered air to merge withfiltered air flowing through the air filter(s). For the reasons notedabove, such electronic appliances may still meet the minimumrequirements imposed by the FCC, NEBS, etc.

FIG. 2 depicts an example of an electronic appliance 200 having brackets202A-B secured thereto. The brackets 202A-B may be attached to opposingsides of the chassis of the electronic appliance 200 or the rack withinwhich the electronic appliance 200 is mounted. The brackets 202A-B canbe attached to the chassis of the electronic appliance 200 with nuts andbolts, screws, magnets, or some other conductive fastener.

Each bracket 202A-B can be designed to receive a mounting frame 204A-B.Here, the mounting frames 204A-B are empty. However, as furtherdescribed below, the mounting frames 204A-B will generally includelaminate curtains when the electronic appliance 200 is in operation. Insome embodiments, the mounting frames 204A-B include one or more guidetubes 206A-B. The guide tube(s) 206A-B can permit a laminate curtain tobe readily installed within the mounting frames 204A-B. For example,each laminate curtain may include collar(s) configured to slip over theguide tube(s) 206A-B. The guide tube(s) 206A-B can also support cablesthat are routed from the interface surface of the electronic appliance200 toward a vertical channel positioned alongside the electronicappliance 200. Thus, the mounting frames 204A-B can assist intransitioning cables into the vertical channel.

The brackets 202A-B, the mounting frames 204A-B, and/or the guide tubes206A-B can be comprised of a conductive material, such as metal,graphite, polymer(s), etc. For example, the mounting frames 204A-B andthe guide tubes 206A-B may be comprised of aluminum. Additionally oralternatively, the brackets 202A-B, the mounting frames 204A-B, and/orthe guide tubes 206A-B can include a conductive plating comprised of,for example, aluminum or copper. For example, the brackets 202A-B may becomprised of stainless steel but may include copper plating.

The brackets 202A-B, the mounting frames 204A-B, and the guide tubes206A-B (collectively referred to as the “mounting components”) can allbe electrically conductive. Thus, the mounting components can beelectrically connected to one another, as well as to the chassis of theelectronic appliance 200 and/or the rack within which the electricappliance 200 is mounted. Such a design effectively grounds the mountingcomponents.

FIG. 3 depicts an example of a laminate curtain 304 that can beinstalled within a mounting frame 302. Similarly, the mounting frame 302can be secured to a bracket 300 that is connected to the chassis of anelectronic appliance. When the mounting frame 302 is affixed to thebracket 300, the mounting frame 302 will typically be arrangedorthogonal to the interface surface of the electronic appliance.

As further described below, the laminate curtain 304 can include aconductive elastomer panel that absorbs spurious electromagneticradiation generated by the electronic appliance, a conductive adhesivefilm disposed along one side of the conductive elastomer panel, and aconductive support frame affixed to the conductive adhesive film. Theconductive support frame of the laminate curtain 304 can be detachablymounted to the mounting frame 302. Here, for example, the conductivesupport frame includes a pair of collars that can slip over the guidetubes of the mounting frame 302.

When electromagnetic radiation leaks through the interface surface ofthe electronic appliance, the laminate curtain 304 will absorb theelectromagnetic radiation. Moreover, because the laminate curtain 304,the mounting frame 302, and the bracket 300 are all electricallyconductive, the electromagnetic radiation can be safely shunted from thelaminate curtain 304 to the chassis of the electronic appliance, whichis grounded.

In some embodiments, the bracket 300 and/or the mounting frame 302 arepainted for aesthetic reasons. Insulating the bracket 300 and/or themounting frame 302 in such a manner may not have any impact onelectrical conductivity.

FIG. 4 depicts an exploded view of a cable management assembly that canbe secured to an electronic appliance 400 adjacent to the interfacesurface to which cables can be connected. More specifically, the cablemanagement assembly can include a pair of laminate curtains 406 that areinstalled within mounting frames 404, as well as an enclosure 408 thatcan be mounted to the mounting frames 404. The cable management assemblycan be secured to brackets 402 attached to opposing sides of the chassisof the electronic appliance 400.

The enclosure 408 can include a bottom panel (also referred to as a“bottom plate”) that prevents cables attached to the interface surfacefrom drooping into the envelope of electronic equipment positioned belowthe electronic appliance 400. For example, a rack will often includemultiple electronic appliances that are stacked on top of one another,so it is important that each electronic appliance only use the spaceadjacent to its own interface surface. The enclosure 408 can alsoinclude a top panel and/or a front panel that connects the top panel tothe bottom panel.

When the enclosure 408 is mounted to the mounting frames 404, theenclosure 408 and the laminate curtains 406 will form asubstantially-sealed chamber adjacent to the interface surface of theelectronic appliance 400. This space may also be referred to as the“cabling space.” The laminate curtains 406 installed within the mountingframes 404 can prevent unfiltered air from flowing into the cablingspace, as well as prevent electromagnetic radiation leaking from theinterface surface from escaping the cabling space. Thus, the technologyintroduced here is able to effectively manage EMI leakage and airflowthrough the CTR of the electronic appliance 400.

As noted above, NEBS may require that air be filtered prior to enteringthe electronic appliance 400. Conventionally, this requirement is oftenwaived or achieved only by meeting the letter of the requirement, ratherthan by actually performing the task as defined by the requirement. Airfilters can become a maintenance issue as air filters must be serviced(e.g., cleaned or replaced) at regular intervals. In some instances, apanel that includes an air filter may be attached to the front of anelectronic appliance. However, the panel, which becomes an integral partof the electronic appliance during the certification process, representsan extremely large hole through which electromagnetic radiation canescape.

FIG. 5 depicts an example of an enclosure 500 that includes multiple airfilters 502A-B and multiple EMI suppression panels 504. While theenclosure 500 shown here includes multiple air filters and multiple EMIsuppression panels, other embodiments could include a single air filterand/or a single EMI suppression panel. For example, some embodiments ofthe enclosure 500 include multiple air filters and a single EMIsuppression panel that at least partially overlaps the multiple airfilters.

The EMI suppression panels 504 may be arranged behind the air filter(s)502A-B to further control electromagnetic radiation that has nototherwise been attenuated. Together with one or more laminate curtains,the EMI suppression panels 504 can ensure that an electronic appliancewill meet the pertinent limits on electromagnetic radiation.

The enclosure 500 can also include air filter(s) 502A-B that ensure airentering the electronic appliance through the interface surface isfiltered. The air filters 502A-B may be disposable air filters that arereadily replaceable by an end user responsible for servicing theelectronic appliance. In some embodiments, EMI suppression panels 504are arranged behind the air filters 502A-B such that the EMI suppressionpanels 504 at least partially overlap the air panels 502A-B. The EMIsuppression panels 504 may be, for example, suppression filters thatprovide electromagnetic noise suppression. Suppression filters can havedifferent thicknesses, designs (e.g., honeycomb-shaped wells), etc.,based on the characteristics of the electromagnetic radiation intendedto be shielded. For example, if the data transfer speed of an electronicappliance increases, a designer may select a new suppression filterhaving a larger thickness, smaller honeycomb-shaped well size, etc.

FIGS. 6-8 depict several different views of a laminate curtain assembly600. More specifically, FIG. 6 depicts a laminate curtain 604 installedwithin a mounting frame 602. FIG. 7 depicts a front perspective view ofthe laminate curtain 604 prior to installation within the mounting frame602, while FIG. 8 depicts a rear perspective view of the laminatecurtain 604 prior to installation within the mounting frame 602.

Laminate curtain assemblies may be used by themselves in some instances(i.e., without an enclosure having a top panel, bottom panel, and/orfront panel). In such embodiments, a laminate curtain assembly may beused to guide airflow through an electronic appliance, suppresselectromagnetic radiation leaking from the electronic appliance, etc.

In some embodiments, the laminate curtain 604 is fixedly installedwithin the mounting frame 602. Thus, in order to remove or replace alaminate curtain 604, an end user may be required to remove the mountingframe 602 as well.

In other embodiments, the laminate curtain 604 is readily removable fromthe mounting frame 602. Here, for example, the laminate curtain 604includes a pair of collars that can slip over the guide tubes of themounting frame 602. Consequently, the laminate curtain 604 could bereplaced or upgraded as necessary. For example, if fewer cables are tobe attached to the interface surface of a network appliance, then a newlaminate curtain may be installed to avoid having electromagneticradiation leak through openings in a laminate curtain that werepreviously filled by cables. As another example, if the data transferspeed of an electronic appliance increases, then a new laminate curtaindesigned to capture a different frequency range of electromagneticradiation may be installed.

FIG. 9 depicts an example of a laminate curtain 900 for suppressingelectromagnetic radiation leaking from the chassis of an electronicappliance. The laminate curtain 900 can include several layers that areresponsible for performing different tasks.

For example, a conductive elastomer panel 904 can be configured toabsorb spurious electromagnetic radiation generated by the electronicappliance. More specifically, the conductive elastomer panel 904 canform a ground plane that catches electromagnetic radiation leaking fromthe chassis of the electronic appliance, and then shunts theelectromagnetic radiation to ground. Electrically-conductive elastomerscan provide excellent mechanical and electromagnetic shieldingproperties, and electrically-conductive elastomers can be used in a widerange of operating temperatures. The conductive elastomer panel 904 maybe comprised of a microwave absorber material in an extruded, molded,formed, or printed format. The conductive elastomer panel 904 isgenerally designed to perform over a large range of electromagneticradiation frequencies. Conductive elastomer panels can be cut todifferent lengths, widths, and/or thicknesses based on the intendedapplication (e.g., whether the laminate curtain will be used inconjunction with an enclosure). Conductive elastomer panels can also bedesigned to be fairly rigid. Performance of a conductive elastomer panelcan vary based on the thickness, material formula, etc. Moreover,performance is typically optimized for a specified frequency range, andthus may fall off rapidly beyond the specified frequency range. Severalexamples of microwave absorber materials are provided in Table I.

TABLE I Examples of microwave absorber materials. RepresentativeRepresentative Reflectivity Material Frequency Range ThicknessPerformance Conductive Foam 20 MHz-10 GHz 2 mm >100 dB (e.g., ParkerSoft- Shield 3500) Conductive Foam 20 MHz-10 GHz 3 mm >90 dB (e.g.,Parker Soft- Shield 4850) Conductive Foam 200 MHz-10 GHz  3.2 mm >90 dB(e.g., Laird 5233)

The conductive elastomer panel 904 typically includes a conductiveadhesive film that covers at least a portion of one surface. Theconductive adhesive film may securely bond the conductive elastomerpanel 904 to a support frame 908. The support frame 908 may be, forexample, a laser-cut piece of sheet metal to which one or more guidetubes 910 have been welded to form a permanent, electrically-conductiveattachment. In some embodiments the support frame 908 and the guidetubes 910 are comprised of an electrically-conductive material, while inother embodiments the support frame 908 and the guide tubes 910 areplated with an electrically-conductive finish.

The conductive adhesive film may extend across an entire side of theconductive elastomer panel 904. However, the support frame 908 may onlymake contact with a relatively small percentage of the conductiveadhesive film. Any remaining exposed adhesive may be covered with one ormore stiffener components 906. The stiffener component(s) 906 may becomprised of, for example, plastic, glass, rubber, etc. The stiffenercomponent(s) 906 add stiffness to the laminated curtain 900. This mayhelp keep the laminated curtain 900 relatively flat, especially when nocables are passing through.

In some embodiments, the laminate curtain 900 also includes aradiation-absorbing panel 902 configured to absorb electromagneticradiation of a specified frequency. The radiation-absorbing panel 902can be comprised of a material (also referred to as a“radiation-absorbent material”) that is designed to absorb incidentradiofrequency (RF) electromagnetic radiation as effectively aspossible. Unlike the conductive elastomer panel 904, theradiation-absorbing panel 902 is typically engineered to performoptimally at a relatively narrow range of electromagnetic radiationfrequencies. For example, a radiation-absorbing panel 902 may bedesigned to absorb electromagnetic radiation corresponding to afrequency of 97 gigahertz (GHz). However, a radiation-absorbing paneltuned to a particular frequency (e.g., 97 GHz) will not absorb theelectromagnetic radiation of nearby frequencies (e.g., 95 GHz) verywell, and will not absorb the electromagnetic radiation of distantfrequencies (e.g., 87 GHz) at all. Performance of a radiation-absorbingpanel 902 can vary based on the material formula. Moreover, performanceis typically optimized for a center frequency, and thus may fall offrapidly on either side of the center frequency. Several examples ofradiation-absorbing panel materials are provided in Table II.

TABLE II Examples of radiation-absorbing panel materials. RepresentativeReflectivity Reflectivity Material Frequency Range CharacteristicPerformance Iron Carbonyl Sheet 2 GHz-20 GHz Wide Spectrum >10 dB (e.g.,Murata EA10) Rubber Sheet (e.g., 2 GHz-18 GHz Tuned ~20 dB at a CumingFLX-1.0, Frequency specified tuned 2.0, etc.) Bands frequency

Typical reflectivity curves of several different radiation-absorbingpanel materials are illustrated in FIG. 10. Here, the reflectivitycurves correspond to radiation-absorbing panel materials tuned to 3 GHz,5 GHz, 10 GHz, and 15 GHz.

In some embodiments, the laminate curtain 900 will include a singleradiation-absorbing panel 902 that is designed to absorb electromagneticradiation of a specified frequency. In such embodiments, if an end userwishes to absorb a different frequency, then the end user will have toreplace the laminate curtain 900.

In other embodiments, the laminate curtain 900 will include multipleradiation-absorbing panels. In such embodiments, eachradiation-absorbing panel can be tuned to a different frequency. Forexample, a laminate curtain 900 may include radiation-absorbing panelscorresponding to 97 GHz, 85 GHz, etc. Performance of aradiation-absorbing panel is generally not tight at higher frequencies.Thus, the higher the frequency, the wider the tuning range can be. Forexample, a radiation-absorbing panel tuned to 96 GHz may also tune out95 GHz and 97 GHz signals. As another example, a radiation-absorbingpanel tuned to 5 GHz may also tune out 4 GHz signals, but might allow 3GHz signals to pass through.

Because the radiation-absorbing panel 902 does not need to beelectrically powered or grounded, the radiation-absorbing panel 902 canbe secured to an adjacent layer with a non-conductive adhesive film. Forexample, a pressure-sensitive adhesive may be all that is needed tosecure the radiation-absorbing panel 902 to the conductive elastomerpanel 904 or another radiation-absorbing panel. The order of the layerswithin the laminate curtain 900 can vary, so long as the conductiveelastomer panel 904 remains electrically coupled to the support frame908.

The layers of the laminate curtain 900 may also be laminated togetherunder sufficient pressure to activate the adhesive layer(s), and thenallowed sufficient time to cure. For example, pressure may be applied toa stack of multiple radiation-absorbing panels that are secured to oneanother with a pressure-sensitive adhesive. As another example, thelaminate curtain 900 may be exposed to a curing assembly for a specifiedduration to ensure that the conductive elastomer panel 904 securelybonds to the support frame 908.

Embodiments of the laminate curtain 900 may include some or all of theselayers, as well as other layers not shown here. For example, someembodiments of the laminate curtain 900 only include the conductiveelastomer panel 904 and the support frame 906.

FIG. 11 illustrates how cables connected to the interface surface of anelectronic appliance can be routed through perforations in a laminatecurtain. Here, for example, orthogonal slots have been laser cut intothe laminate curtain. These slots allow cables of different sizes to beslid through the laminate curtain and neatly dressed into a verticalchannel running alongside the electronic appliance.

FIG. 12 illustrates how the slots in a laminate curtain can form aseries of flaps, which seal as much as possible to ensure maximumcapture of electromagnetic radiation leaking from the electronicappliance. A cable can be easily maneuvered along the slots so that theopening created by the cable can be substantially sealed. The slots canaccommodate cables of varying diameters. For example, a single laminatecurtain may accommodate the passing of both large and small cables.

As noted above, in some embodiments the laminate curtain includes one ormore stiffener components that add stiffness to the laminate curtain.The stiffener component(s) may provide sufficient tension to close eachslot after a cable has been slid through the laminate curtain. This maybe particularly useful when an end user needs to add a new cable behindpreviously-installed cables but wants to avoid removing allpreviously-installed cables to dress in the new cable.

Some embodiments of the laminate curtain can also be modified in thefield prior to installation within a mounting bracket. For example, anend user may wish to create a perforation by removing material along anexisting slot, lengthen an existing slot, or create an entirely newopening in the laminate curtain to accommodate a large diameter cable.If the large cable is removed or moved at a later time, then thelaminate curtain can be replaced with an unmodified laminate curtain.Similarly, if a laminate curtain becomes damaged, then the laminatecurtain can be replaced in the field.

FIG. 13 depicts a flow diagram of a process 1400 for manufacturing alaminate curtain able to suppress electromagnetic radiation leaking fromthe chassis of an electronic appliance. Initially, a manufactureracquires a conductive elastomer panel that is configured to absorbspurious electromagnetic radiation generated by the electronic appliance(step 1301). The conductive elastomer panel is generally designed toperform over a large range of electromagnetic radiation frequencies. Forexample, the conductive elastomer panel may be designed to absorbelectromagnetic radiation frequencies ranging from 50-100 GHz, 100-200GHz, etc.

The conductive elastomer panel can then be secured to a support frame(step 1402). For example, the conductive elastomer panel and the supportframe may be secured together via a conductive adhesive film. Together,the conductive elastomer panel and the support frame form anelectrically-conductive attachment that can be secured to the electronicappliance.

The conductive adhesive film may extend across an entire side of theconductive elastomer panel. However, the support frame may only makecontact with a relatively small percentage of the conductive adhesivefilm. Therefore, in some embodiments one or more stiffener componentsare affixed to the exposed portion of the conductive adhesive film (step1303). Generally, the stiffener component(s) are comprised of anon-conductive material, such as plastic, glass, rubber, etc. Thestiffener component(s) also add stiffness to the laminate curtain inaddition to covering exposed portions of the conductive adhesive film.

One or more radiation-absorbing panels may also be affixed to theconductive elastomer panel (step 1404). Unlike the conductive elastomerpanel, the radiation-absorbing panel(s) are typically engineered toperform optimally at a relatively narrow range of electromagneticfrequencies. For example, the laminate curtain may includeradiation-absorbing panels designed to absorb electromagnetic radiationcorresponding to a frequency of 150 GHz, 125 GHz, 110 GHz, 97 GHz, 85GHz, etc.

The laminate curtain can then be exposed to a curing assembly for aspecified duration (step 1305). The curing assembly can include a lightsource (e.g., an ultraviolet light source) and/or a heat source (e.g., aheat lamp). The laminate curtain may be exposed to the curing assemblyfor a specified duration to ensure that the adhesive layer(s) in thelaminate curtain have solidified. Additionally or alternatively,pressure may also be applied to the laminate curtain. An application ofpressure may be necessary when the laminate curtain includes at leastone pressure-sensitive adhesive layer. For example, pressure may beapplied to a stack of multiple radiation-absorbing panels that aresecured to one another via pressure-sensitive adhesive layers.

In some embodiments, the laminate curtain is cut to create one or moreopenings through which a cable can be guided (step 1406). For example, alaser cutter may create a series of orthogonal slots that allow cablesof different diameters to pass through. Perforations of different sizes,shapes, and/or patterns may be cut into a laminate curtain based onwhich cable(s) are expected to be guided through the laminate curtain.Alternatively, a laminate curtain may be left unmodified. In suchembodiments, an end user may be expected to manually create opening(s)in the laminate curtain.

Unless contrary to physical possibility, it is envisioned that the stepsdescribed above may be performed in various sequences and combinations.For example, the laminate curtain may be cured each time a new layer isadded. Other steps could also be included in some embodiments.

Processing System

FIG. 14 is a block diagram illustrating an example of a processingsystem 1400 in which at least some operations described herein can beimplemented. For example, the processing system 1400 may share acomputer architecture with an electronic appliance to which one or morelaminate curtains are connected (e.g., electronic appliance 100 of FIG.1). As another example, the processing system 1400 may be responsiblefor implementing certain steps of a process for manufacturing laminatecurtains.

The process system 1400 may include one or more processors 1402, mainmemory 1406, non-volatile memory 1410, network adapter 1412 (e.g.,network interfaces), display 1418, input/output devices 1420, controldevice 1422 (e.g., keyboard and pointing devices), drive unit 1424including a storage medium 1426, and signal generation device 1430 thatare communicatively connected to a bus 1416. The bus 1416 is illustratedas an abstraction that represents any one or more separate physicalbuses, point to point connections, or both connected by appropriatebridges, adapters, or controllers. The bus 1416, therefore, can include,for example, a system bus, a Peripheral Component Interconnect (PCI) busor PCI-Express bus, a HyperTransport or industry standard architecture(ISA) bus, a small computer system interface (SCSI) bus, a universalserial bus (USB), IIC (I2C) bus, or an Institute of Electrical andElectronics Engineers (IEEE) standard 1394 bus, also called “Firewire.”A bus may also be responsible for relaying data packets (e.g., via fullor half duplex wires) between components of a network appliance, such asa switching engine, network port(s), tool port(s), etc.

In various embodiments, the processing system 1400 operates as astandalone device, although the processing system 1400 may be connected(e.g., wired or wirelessly) to other devices. For example, theprocessing system 1400 may include a terminal that is coupled directlyto an electronic appliance. As another example, the processing system1400 may be wirelessly coupled to the electronic appliance.

In various embodiments, the processing system 1400 may be a servercomputer, a client computer, a personal computer (PC), a user device, atablet PC, a laptop computer, a personal digital assistant (PDA), acellular telephone, an iPhone, an iPad, a Blackberry, a processor, atelephone, a web appliance, a network router, switch or bridge, aconsole, a hand-held console, a (hand-held) gaming device, a musicplayer, any portable, mobile, hand-held device, or any machine capableof executing a set of instructions (sequential or otherwise) thatspecify actions to be taken by the processing system 1400.

While the main memory 1406, non-volatile memory 1410, and storage medium1426 (also called a “machine-readable medium) are shown to be a singlemedium, the term “machine-readable medium” and “storage medium” shouldbe taken to include a single medium or multiple media (e.g., acentralized or distributed database, and/or associated caches andservers) that store one or more sets of instructions 1428. The term“machine-readable medium” and “storage medium” shall also be taken toinclude any medium that is capable of storing, encoding, or carrying aset of instructions for execution by the processing system 1400 and thatcause the processing system 1400 to perform any one or more of themethodologies of the presently disclosed embodiments.

In general, the routines that are executed to implement the technologymay be implemented as part of an operating system or a specificapplication, component, program, object, module, or sequence ofinstructions (collectively referred to as “computer programs”). Thecomputer programs typically comprise one or more instructions (e.g.,instructions 1404, 1408, 1428) set at various times in various memoryand storage devices in a computer, and that, when read and executed byone or more processing units or processors 1402, cause the processingsystem 1400 to perform operations to execute elements involving thevarious aspects of the disclosure.

Moreover, while embodiments have been described in the context of fullyfunctioning computers and computer systems, those skilled in the artwill appreciate that the various embodiments are capable of beingdistributed as a program product in a variety of forms, and that thedisclosure applies equally regardless of the particular type of machineor computer-readable media used to actually effect the distribution.

Further examples of machine-readable storage media, machine-readablemedia, or computer-readable (storage) media include recordable typemedia such as volatile and non-volatile memory devices 1410, floppy andother removable disks, hard disk drives, optical disks (e.g., CompactDisk Read-Only Memory (CD ROMS), Digital Versatile Disks (DVDs)), andtransmission type media such as digital and analog communication links.

The network adapter 1412 enables the processing system 1400 to mediatedata in a network 1414 with an entity that is external to the processingsystem 1400, such as a network appliance, through any known and/orconvenient communications protocol supported by the processing system1400 and the external entity. The network adapter 1412 can include oneor more of a network adaptor card, a wireless network interface card, arouter, an access point, a wireless router, a switch, a multilayerswitch, a protocol converter, a gateway, a bridge, bridge router, a hub,a digital media receiver, and/or a repeater.

The network adapter 1412 can include a firewall which can, in someembodiments, govern and/or manage permission to access/proxy data in acomputer network, and track varying levels of trust between differentmachines and/or applications. The firewall can be any number of moduleshaving any combination of hardware and/or software components able toenforce a predetermined set of access rights between a particular set ofmachines and applications, machines and machines, and/or applicationsand applications, for example, to regulate the flow of traffic andresource sharing between these varying entities. The firewall mayadditionally manage and/or have access to an access control list whichdetails permissions including for example, the access and operationrights of an object by an individual, a machine, and/or an application,and the circumstances under which the permission rights stand.

Other network security functions can be performed or included in thefunctions of the firewall, including intrusion prevention, intrusiondetection, next-generation firewall, personal firewall, etc.

As indicated above, the techniques introduced here implemented by, forexample, programmable circuitry (e.g., one or more microprocessors),programmed with software and/or firmware, entirely in special-purposehardwired (i.e., non-programmable) circuitry, or in a combination orsuch forms. Special-purpose circuitry can be in the form of, forexample, one or more application-specific integrated circuits (ASICs),programmable logic devices (PLDs), field-programmable gate arrays(FPGAs), etc.

Note that any of the embodiments described above can be combined withanother embodiment, except to the extent that it may be stated otherwiseabove or to the extent that any such embodiments might be mutuallyexclusive in function and/or structure.

Although the present invention has been described with reference tospecific exemplary embodiments, it will be recognized that the inventionis not limited to the embodiments described, but can be practiced withmodification and alteration within the spirit and scope of the appendedclaims. Accordingly, the specification and drawings are to be regardedin an illustrative sense rather than a restrictive sense.

1. An electromagnetic interference (EMI) shielding system for anelectronic appliance, the EMI shielding system comprising: a pair ofbrackets connected to opposite sides of an electronic appliance chassis;and a pair of laminate curtain assemblies, each removably connected to aseparate bracket of the pair of brackets, wherein each laminate curtainassembly of the pair of laminate curtain assemblies includes a laminatecurtain configured to absorb electromagnetic radiation leaking from aninterconnect surface of the electronic appliance chassis that isorthogonal to the opposite sides of the electronic appliance chassis,and a mounting frame within which the laminate curtain is mounted. 2.The EMI shielding system of claim 1, further comprising: an enclosuremounted to the pair of laminate curtain assemblies, wherein theenclosure includes a top panel, a bottom panel, and a front panelconnecting the top panel to the bottom panel.
 3. The EMI shieldingsystem of claim 2, wherein the enclosure and the pair of laminatecurtain assemblies together form a substantially-sealed chamber adjacentto the interconnect surface of the electronic appliance chassis.
 4. TheEMI shielding system of claim 3, wherein a cable connected to theinterconnect surface of the electronic appliance chassis is routed fromthe substantially-sealed chamber to an external environment through aperforation in the laminate curtain of a specified laminate curtainassembly.
 5. The EMI shielding system of claim 2, further comprising: anair filter configured to filter air entering the electronic appliancechassis.
 6. The EMI shielding system of claim 5, wherein the air filteris disposed within the top panel, the bottom panel, or the front panelof the enclosure.
 7. The EMI shielding system of claim 5, furthercomprising: an EMI suppression panel that at least partially overlaysthe air filter.
 8. The EMI shielding system of claim 1, wherein thelaminate curtain of each laminate curtain assembly is removable from thecorresponding mounting frame.
 9. The EMI shielding system of claim 1,wherein the laminate curtain is comprised of: a conductive elastomerpanel designed to absorb electromagnetic radiation corresponding to aspecified frequency range; a conductive support frame; and a conductiveadhesive layer that electrically connects the conductive elastomer panelto the conductive support frame.
 10. The EMI shielding system of claim9, wherein the laminate curtain is further comprised of: a stiffenercomponent affixed to the conductive adhesive layer.
 11. The EMIshielding system of claim 1, wherein the laminate curtain includes aplurality of slots through which cables connected to the interconnectsurface of the electronic appliance chassis can be routed.
 12. Alaminate curtain comprising: a conductive elastomer panel configured toabsorb electromagnetic radiation leaking from an electronic appliancechassis; a conductive support frame configured to be connected to theelectronic appliance chassis; and a conductive adhesive film thatsecures the conductive elastomer panel to the conductive support frame;wherein the conductive support frame is configured to shunt at least aportion of the electromagnetic radiation absorbed by the conductiveelastomer panel to the electronic appliance chassis, so that the atleast a portion of the electromagnetic radiation flows from theconductive elastomer panel to the conductive support frame via theconductive adhesive film.
 13. The laminate curtain of claim 12, furthercomprising: a plurality of stiffener components affixed to theconductive adhesive film.
 14. The laminate curtain of claim 12, furthercomprising: a radiation-absorbing panel configured to absorbelectromagnetic radiation of a specified frequency; and an adhesive filmthat secures the radiation-absorbing panel to the conductive elastomerpanel.
 15. The laminate curtain of claim 14, wherein the adhesive filmdisposed between the radiation-absorbing panel and the conductiveelastomer panel is not electrically conductive.
 16. The laminate curtainof claim 14, wherein the radiation-absorbing panel is one of a pluralityof radiation-absorbing panels included in the laminate curtain.
 17. Thelaminate curtain of claim 16, wherein each radiation-absorbing panel ofthe plurality of radiation-absorbing panels is designed to absorbelectromagnetic radiation of a different frequency. 18-23. (canceled)